Neanderthals Used Birch Tar as Ancient Antibiotic, Study Finds

For millennia, birch bark has been a crucial resource for people in the Northern Hemisphere, used for canoes, baskets, and even writing surfaces. Now, evidence suggests our Neanderthal cousins recognized another remarkable property of this tree: its potential as a medicine. A new study indicates Neanderthals may have harnessed birch tar – a sticky substance created from heating birch bark – not just as a prehistoric glue for toolmaking, but as a topical antibiotic to treat wounds.

The research, published in PLoS One, builds on archaeological findings of birch tar at numerous Neanderthal sites. While previously understood as a key component in hafting – the process of attaching stone points to wooden shafts to create more effective tools – scientists are now exploring its potential medicinal applications. The study demonstrates birch tar’s effectiveness against Staphylococcus aureus, a common bacterium responsible for skin infections.

Birch Tar Production: Replicating Ancient Techniques

The team, led by Tjaark Siemssen, a graduate student at the University of Oxford, meticulously recreated birch tar using methods likely employed by Neanderthals. They collected bark from European birch trees (Betula pendula and Betula pubescens) and employed three distinct extraction techniques. These included distillation in stacked tins, a method used by the Mi’kmaq people of Canada, as well as techniques involving clay mounds and condensing smoke on stone surfaces – methods hypothesized to have been used by Neanderthals. Specialized hearths were likely used for this process, according to archaeological evidence.

Antimicrobial Properties: Targeting Gram-Positive Bacteria

To assess the tar’s antimicrobial capabilities, researchers incubated samples with both Staphylococcus aureus (a gram-positive bacterium) and Escherichia coli (a gram-negative bacterium). The results were striking: nearly all tar samples exhibited bactericidal action against S. Aureus, with one sample demonstrating particularly potent effects. Yet, none of the samples showed any activity against E. Coli, leading the researchers to conclude that birch tar selectively targets gram-positive bacteria. This selectivity is likely due to the chemical composition of the tar, rich in phenolic derivatives like catechols and guaiacols, which disrupt the cell walls of gram-positive bacteria.

Indigenous Knowledge Validated by Science

This discovery isn’t entirely new. Several indigenous communities, including the Yakut, Saami, and Mi’kmaq, have long utilized birch tar for wound dressing and medicinal purposes. Siemssen notes that observing the Mi’kmaq’s traditional use of birch bark sparked the scientific investigation. “Seeing birch bark being used for something so completely different than what we’ve seen so far in the archaeological record made us investigate it scientifically,” he explains. The study effectively validates this traditional knowledge with rigorous scientific evidence.

Implications for Understanding Neanderthal Healthcare

The findings offer a fascinating glimpse into the potential healthcare practices of Neanderthals. While the Neanderthals disappeared from the archaeological record around 42,000 years ago, recent research suggests they were far more sophisticated than previously believed, engaging in activities like burying their dead, creating art, and crafting complex tools. Evidence from sites in Italy and Germany further supports the use of birch tar by Neanderthals.

Michael Petraglia, an evolutionist at Griffith University, Australia, who was not involved in the study, describes the research as “impressive.” He highlights the strength of combining scientific experimentation with indigenous knowledge, leading to “reasonable judgments about Neanderthal behavior and lifestyles.” Petraglia suggests that given the Neanderthals’ extensive use of birch tar for toolmaking, it’s plausible they recognized its medicinal properties. However, he cautions that “additional biological and archaeological evidence shall be needed” to reach a definitive conclusion.

Practicality and Efficiency: A Byproduct Benefit

The study also highlights the practicality of using birch tar for medicinal purposes. A mere 0.2 grams of tar can cover 100 square centimeters of skin, meaning sufficient quantities for topical application could be readily obtained as a byproduct of the tool-hafting process, regardless of the specific extraction method used. This suggests that Neanderthals could have easily accessed and utilized birch tar for wound care without requiring a dedicated effort.

Future Research and the Neanderthal Pharmacopoeia

While this study provides compelling evidence for the potential medicinal use of birch tar, further research is needed to fully understand the extent of Neanderthal healthcare practices. Scientists are now exploring other plant materials found at Neanderthal sites to identify potential additional remedies. The combination of archaeological evidence, experimental studies, and collaboration with indigenous communities promises to reveal a more complete picture of how our extinct relatives managed their health and well-being. The next steps involve further analysis of archaeological sites for evidence of intentional medicinal use, as well as investigating the potential synergistic effects of birch tar with other plant-based compounds.